Yao Chenguo

A Review on Molecular Dynamics Simulation for Biological Effects of Pulsed Electric Field

In recent years, the electric field in the application of biological research has become a hot spot, However, the mechanism still lags behind the experimental study. Molecular dynamics simulation could not only get the atomic trajectory, but also get a variety of observation like to do the same experiment. Therefore we could choose molecular dynamics simulation to study the mechanism. This article discusses the basic principles of the molecular dynamics simulation; comprehensive analysis research status and recent applications of molecular dynamics simulation in electric field biological effect at home and abroad. In particular, we have a detailed description and analysis of the biological effects of pulsed electric field of molecular dynamics simulation results, such as nanopore formation at membranes in response to a high-intensity (~0.5 V/nm), nanosecond electric pulse. And On this basis, the development trends and application prospects of molecular dynamics simulation on pulsed electric field in the biological effects is put forward.

Programmable voltage regulating method for high voltage DC power supply based on digital potentiometer and linear photoelectric coupling

In order to solve the disadvantages caused by mechanical slide rheostat that they were big errors and low precision, a novel voltage regulation method for high voltage DC power supply was introduced. The key of this method were digital potentiometer Maxim 5455 and linear photoelectric coupling LOC110, and application programs were compiled using Visual Basic which was graphical compiling language, furthermore the communication between exterior and computer was carried out by ICP7044D module, in consequence the output value of high voltage DC power supply could be regulated with computer. The measured results showed that this method could accurately, conveniently and rapidly regulate the output value of high voltage DC power supply.

The optimal Design of Electrod Array using Electroporation Based on the Finite Element

With the promotion of the electroporation therapy clinical application, how to design an electrode with a lower voltage level and distribution and high intensity electric field in order to achieve the optimal treatment of tumors. In this paper, FEMLAB finite element analysis software is used for the needle electrodes in biological tissue electroporation for electric field simulation, the simulation results show that: voltage amplitude, the distance between positive and negative electrode needle, needle electrodes and the number of needle electrodes, and other distribution methods will affect the effective electric field area of biological tissue. By comparing different needle electrodes corresponds to the structure of the electric field distribution uniformity, the effective electric field (Eeff) radius of coverage as well as the size of the rated output voltage power supply requirements, We has designed optimal structure of the needle electrodes (seven plum blossom-shaped electrodes acupuncture), which provide a theoretical basis for the production of needle electrodes.

Simulation and Calculation of Electric Field Power on Plasma Membrane Exposed to Steep Pulsed Electric Field

The basic characteristic of the electric field is that it has a powerful function on the materials put in it. Under this power, both within and outside the cell membrane and its surface have a strong electric field distribution, at the same time, due to the difference among the dielectric constant of the cell membrane and the extracellular fluid and the cytoplasm, there must be a force acts on the cell surface depending on the electromagnetic field theory. In order to a further exposition of the irreversible breakdown mechanism on the steep pulsed electric field to the malignant cells, this article using the MATLAB takes the malignant tumor cells and the normal cells as the objects of study respectively, on the theory calculates and simulates the forces suffered by the cells separately under the steep pulsed electric field, and gives the results of a comparative analysis. This study finds that there is a cross traction along the membrane plane in addition to the compression strength perpendicular to the surface of it. The lateral force will reduce the tension of the film significantly, leading to electroporation and rupture on the cell membrane. The tensity changing quantity that the same electric field (6.7times107 V/m) produces in normal cells is 2 m Nm-1, while in tumour cells it is 10 m Nm-1. It can be seen that the strength towards the malignant tumor cells is 1 magnitude bigger than that towards the normal cells.